Jockey

Filled, with terminal.

Investigate the working principle of circuit breaker type fuse, with this demonstration model. The apparatus is built on a robust plastic base and includes resistive loads to simulate external wiring circuits. Applications of the thermal response of bimetal strips and also electromagnetism (movement from a solenoid) are clearly demonstrated in this model.
When a 12VDC supply is connected (not supplied) the LED lights to show that current is flowing in the external circuit and the bi-metal strip can be seen to bend as its heater coil raises the temperature. After a few minutes the bending is sufficient to trip the mechanism and the current path is broken. At any current selection a short circuit situation can be initiated by pressing the red button and this produces an immediate response from the solenoid to disconnect the supply.

Includes:

• Copper Coil – With screw clamps to hold a nail for the nail melting demonstration.
• Nails – Steel flat-headed nails 65 x 3 mm or 2½ x 1/8 inch, some with a central groove making the nail thinner at that point.
• Solid and Split Aluminium Rings-Two solid and one split for the ring-launching demonstration.
• Solder Trough – Effectively a single turn coil in the form of a circular trough. Approximately 300 mm of solder is formed into a 50 mm dia meter circle to lie in the trough.